Title

Browning Apples

Problem Scenario

People would want to study this because it could help them keep their apples fresh for a longer time.

Broad Question

How can I stop apples from browning?

Specific Question

What can I put on apples to keep them from browning?

Hypothesis

Different liquids will have different effects on the apple slices. Lemon juice will have the best effect on the apples.

Graph of Hypothesis

Variables

Independent Variable:

liquid put on cut apple slices

Dependent Variable:

Time it takes for apples to brown

Variables That Need To Be Controlled:

• size of apple slice
• amount of liquid put on apple

Vocabulary List That Needs Explanation

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General Plan

For my experiment I will cut an apple into 10 equal slices with an apple slicer. I will put the liquid in a spray bottle and spray each slice. Second time I will dip it rather than spray it. Then put them on a plate. I will time them each individually till they start to brown. I will average all 10 times and use that number for my result.

Potential Problems And Solutions

My brother could come over and eat my apples. To prevent this I could do my project when my brother isn't home. Another problem is the apples could start browning before i put the liquid on. To solve this problem I would do this really fast.

Safety Or Environmental Concerns

Experimental Design

What is your experimental unit?:

Apples

Number Of Trials:

2

Number Of Subjects In Each trial:

10

Number of Observations:

1

When data will be collected

Feb. 16, 2012

Where will data be collected?:

My Home

Resources and Budget Table

Item	[[#|Number]] needed	Where I will get this	Cost
Apples	12 apples
Water
Salt
Sprite	1 bottle
Lemon Juice	6 lemons (juiced)
Spray Bottle	1

Detailed Procedure

1. Put liquid in a spray bottle
2. Put apple on plate
3. Cut apple into 12 slices
4. Spray each slice once on each side
5. Leave out and time with a timer
6. Average all 12 times
7. Add to chart
8. Second time follow same instructions

Diagram

Photo List

Time Line

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Data Table

	nothing	lemon-lime soda	lemon juice	water	salt water
Test #1	15:17:1	18:31:96	6hr+	25:37:1	8hr+
Test #2	19:06:71	17:38:5	6hr+	24:18:61	8hr+

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Data Analysis

All Raw Data

Graphs

See above

Photos

Results

Salt Water worked the best out of all the liquids. Lemon juice was up there but there was a few brown spots but not enough to classify as browned. Salt water was stopped at 8 hours but was still fresh. Lemon juice was left out 6 hours and still pretty fresh.

Conclusion

How can you prevent apples from browning? I thought lemon juice would work the best and all of them would have a different time. Salt water and lemon juice were both up there. While most people think lemon juice works the best, salt water actually beat it in a way but also tied. Salt water made it super bright and it didn't brown. Although lemon juice had a few brown spots around the bruises, it was just as white.

Discussion

The lower ones (Nothing, Lemon-lime soda, water) all ranged around the twenty area. The dependent variable depended pretty strongly on the Independent one. The answer to my question was salt water/lemon juice. I didn't have any problems. This could be improved by having a more specific time to stop when it is considered "brown".

Benefit to Community and/or Science

Background Research

Apples contain an enzyme that reacts to both oxygen and and iron found in the apple. It will not work unless it has that oxygen. This is why they only turn brown after you slice them. This is what gives it the brown discoloration on the skin.

References

Abstract

Salt water worked the best in preventing apples from turning brown. Lemon juice worked just as good except for a few brown spots around the bruises. All the others will stay fresh for around 15-20 minutes.